In my Enameling 101 post, we discussed safety and supplies. This post will cover the difference between kiln and torch firing, as well as the importance of ample practice for a successful outcome.
The thought that little grains of powdered glass sitting on top of a piece of metal can transform into a vibrant piece of art simply by adding the right amount of heat is exciting! You watch as the glass slowly melts, fusing to the metal, causing the transformation to begin, and voilà…beauty!
Getting to this final outcome requires a basic procedure for firing your pieces. Enamel is applied to a piece of metal that has been cleaned and prepared for the process. The piece is then heated to approximately 1500 degrees by use of either a torch or kiln, which causes the enamel to melt, and fuse to the metal. Sound pretty simple? It really is!
First, you’ll need to determine how you’ll fire your pieces.
The decision of whether to fire your enamels with a kiln or a torch is usually based on the following criteria: Cost, size of your work space, size of the piece(s) to be fired, and future use of equipment. If you’re unsure, here is an easy rule of thumb: If you’re building up enamel in multiple layers, use a kiln. If you’re working with single or fine layers that can fire quickly, use a torch with a tripod. Let’s take a look at each method individually to get a better idea of the distinctions.
Selecting an Enameling Kiln
When selecting a kiln, I look for a few features:
- It should be programmable to at least 1600°F
- The door should open to the side rather than to the top. You will want to quickly and easily insert and remove your enamel pieces. A top-loading kiln makes this process cumbersome and can lead to spilled enamel powder, dropped hot pieces, or a delay in removing the fired piece fast enough.
Rio Grande carries several great kilns that work within these guidelines and fit most everyone’s budget. These kilns can also be used for metal clay, glass fusing, and to anneal metal. If you purchase one of these kilns, you’ll definitely be making an investment in a multi-purpose piece of equipment that will last for years.
When firing your pieces in a kiln, adjustments to firing times will be based on your particular kiln, as well as the enamel being used, type and thickness of metal, and size of piece. It isn’t likely for two kilns, even the same model, to fire exactly alike. Because of this, you cannot base your firing times on what someone else has done. Get to know your kiln. Work on test pieces to keep as color samples. To master an understanding of firing times, it’s necessary to practice, practice, practice!
Steps for Kiln Firing
- Before firing pieces, pre-heat your kiln to 1500°F. If your kiln includes user-defined programming, set the hold time for 6-8 hours to ensure enough working time so the kiln won’t shut off in the middle of a project.
- While the kiln is heating, prepare your metal. In order for enamel to have permanent adhesion the metal must be cleaned properly. Doing so prevents the enamel from cracking or popping off the surface during cooling. Once clean, don’t touch the surface of the metal. (I’ll cover this process further in my next post.)
- Apply the first layer of your design. Then, transfer your piece to the steel mesh firing rack and/or trivet, to be fired.
- Wearing kiln safety glasses and a heat resistant glove, use a steel firing fork or spatula to place the firing rack in the center of the kiln as quickly as possible and carefully close the door. Doing this quickly will prevent the kiln temperature from dropping too much. (Tip: It’s a great idea to practice doing this quickly while the kiln is still cold!)
- You can set a timer for 2 minutes as a guideline only. Experience will teach you how to recognize the different texture stages so you do not under or over fire your pieces.
- When the piece has fired to the correct texture, (again, wearing your safety equipment) use your steel fork or spatula to remove the firing rack from the kiln; set it on a heat protected surface, and let the piece cool down slowly.
As you begin with enamels, you might decide you’d first like to try working with a torch before investing in a kiln. You can use just about any type of torch to fuse enamel to your metal pieces, but a butane torch is best for small pieces.
Steps for Torch Firing
- You’ll want to work on a heatproof work surface when torch firing your enamel pieces. This way, if any of the hot glass slides off of the piece, it will not create a fire hazard. Getting a few inexpensive ceramic tiles from your local hardware store, which you can set on top of your workbench or counter, is a great way to protect your work surface. I have three, 15” square, ceramic tiles that are set up side-by-side. My tripod is placed on the center tile, leaving the other two tiles for setting down tools or hot pieces to cool.
- Just like kiln firing, you’ll want to use all the appropriate safety equipment when torch-firing enamels. In addition to the safety glasses and heat resistant gloves, you should also use a face mask specifically approved for enameling, especially if working with lead-based enamels. Finally, be sure to work in a well-ventilated area, whether you’re working with leaded or non-leaded enamels. Keep in mind that non-leaded enamels are much safer for torch firing.
- Now that your firing area is set up, you can prep your metal and begin the first layer of your design.
- Place your prepared piece on a trivet. Then, set the trivet on the mesh firing screen that is resting on your tripod.
- Now you’re ready to light your torch and start firing. The torch flame should be underneath the mesh firing screen. Begin to move the torch in an even, gentle, circular motion. As the piece heats up, you’ll begin to see the various stages the enamel goes through.
- When you’ve reached the desired stage, move the flame away from your piece and turn off the torch. At this point, let your newly fired piece cool down. Once cool, you can either add another layer of enamel to fire, or if the piece is completed, prepare for finishing.
Even if you plan to do all of your enameling in a kiln, take the time to practice firing some pieces with a torch. This practice will help you become familiar with the sugar-coat stage, the orange-peel stage, and the fully-fused stage and it’ll help you recognize a piece that is over fired. Stay tuned to The Studio for future enameling blog posts in which I’ll explain these stages in greater detail.
They say that practice makes perfect, and when it comes to enameling this adage is so true! The more you practice, the more you’ll be rewarded with beautiful, perfectly-fired pieces.
Another great way to sharpen your skills is by taking a class with a seasoned enameler! Keep an eye out for upcoming classes here at Rio Grande.